so after we have our itinerary set (Busan, Suncheon, Yeosu, Jeonju & Seoul) I'm having trouble figuring out where to stay in Busan. Nampo dong seems like a good area but it looks like traveling to other areas of the city will take quite a long time (about an hour to Haeundae for example).
Syemeon seems a lot more centrally located but the hotel I find there are quite pricey.
what would you recommend? we have a budget of around 70$ per night (no guesthouses or hostels).

and what's the deal with all those hotels that insist on putting glass doors between shower/toilet and room? I literally found tons of hotels like that that fit the price but we can't stay there because of that. so frustrating.

For my purposes, the Seomyeon area seemed ideal – it is within a few minutes walk of 2 different subway stops (including one with elevator access) and very near some tasty restaurants in a lively section of town. I stayed at the Hotel Angel, with is suited my needs well, but it is quite basic. From Seomyeon, it will still take some time to get to Haeundae.... I think where to stay probably depends on what YOU want to see and experience.

I stayed in two different areas, one before Jeju and one after.

I started at Haeundae, even though I am not a beach person, and it was fine for a couple of nights. I was in the Ibis Budget Ambassador with a sea view room.

When I returned I stayed at the Uniqstay Hostel and Suites in a private room. Behind the Lotte Dept. store in Seomyeon with a metro station underneath. Pretty bare bones.

I preferred Haeundae, but Seomyeon was more convenient for getting around.